Surface condenser



Jah. 22, 1929. 1,700,106

R.N.'EHRHART SURFACE CONDENSER Filed Jan. 1o. 1921 Patented Jan. 22, 1929.

UNITED STATES PATENT OFFICE.

RAYMOND N. EHRHART, 0F JEANNETTE, PENNSYLVANIA, ASSIGNOR TO ELLIOTT COMPANY, OF PITTSBURGH, PENNSYLVANIA, lA CORPORATION 0F FENNSYL'VANIA.

SURFACE CONDENSER.

Application led January 10, 1921.

Figure l is a vertical cross section of a surface condenser embodying my invention, the view being partly conventional;

Figure 2 is a comparative diagram illustrating one of the advantages of my invention;

Figure 3 is a longitudinal vertical section of a condenser embodying the invention.

My invention has relation to surface condensers, and is designed to improve the eiliciency of such condensers, particularly in the larger sizes thereof.

As a general rule, apparatus used in the generation of power or in connection therewith increase in etliciency as the size increases. This is particularly true with generating apparatus, such as steam turbines, engines, etc. Surface condensers, which con-` dense the steam from engines or turbines, however', have a tendency to decrease in efliciency as the size increases. In the ordinary construction' of such condensers as have heretofore been used, the cylindrical shell of the condenser is more or less completely iilled with a bank or nest of tubesthrough which water is circulated, the steam flowing through the shell around the tubes downwardly Jfrom a steam'inlet at the top, the air and other noncondensable gases being taken olf at a point at or near the bottom of the condenser. It will be readily seen that as the diameter of the condenser increases, the length of the flow path through the banks of tubes also increases, and as the steam has to traverse the entire nest of tubes, the losses in pressure would increase from the steam inlet'fof the condenser to the point of air oitake, in accordance with the increase in the length of the low path. The result is that there is considerably less loss in pressure in a small condenser than in a large one. In other words, if the same vacuum is maintained at the air outlets of both large and small condensers, a better vacuum will be maintained in the steam inlet of the small condenser, with the proportions of loadings the same, since there will be less pressure absorbed in flowing over the relatively short flow'path in the smaller condenser as compared with the.v

longer flow path in the larger condenser.

In order that the condenser may have the Greatest eiliciency, the area at dilerent points 1n the flow path should gradually diminish from the steam inlet to the point of air oil'- take, so that relatively the same velocity of Serial No. 436,052.`

flow is kept up throughout the flow zone of the condenser. This is not possible in the ordinary condensers heretofore used, in which the maximum area is at the central horizontal plane of the condenser and diminishes in both directions from such plane. that the curve representing the areas of the iiow path in the direction of the flow through such condenser has substantially the form shown by dotted line ct-a in Figure 2 where- 'as for the greatest efficiency, this curve should be represented by the line b-b in Figure 2. It is possible to modify the line a-a considerably by cutting steam lanes through the upper portion of the condenser and by crowding the tubes very close together in the lower portion of the condenser; but even with these changes, the desired gradation of area is only approximate.

The object ot my inventionis to provide a construction particularly applicable-to large condensers and by means of which the etliciency can be maintained in the above respects, notwithstanding the increase in size.

In carrying out my invention, I arrange the tubes in an upper nest or bank 2, of substantially semicircular torni in cross section, and a lower nest or bank 3. Baiiies l are provided which separate the lower nest or bank into two approximately triangular 'sections The result is these baiiles' forming a flow passage 5 for the air and other non-condensible gases from the tubes ot the upper nest down between the two sections of the tubes of the lower nest. Preferably, these battles terminate at a point somewhat above the lowest tubes of the lower nest. 6 designates the usual otake 'lor air and other non-condensible gases.

The baiiies 4e are preferablyy oppositely inclined, as shown, wherebycondensate from the upper nest will pass therefrom into a chamber in open communication with the vapor inlet of the condenser.

It will be noted that the tubes of the upper nest are so arranged that there is a flow space or chamber 7, downwardly around each side of this nest, around the outer edges of the horizontal portions ot the baflies 4, and in -open communication with the vapor inlet of tially as represented by the line b-J) in Figure 2.

I preferably provide for a water circulation through the tubes of the condenser in which the water first flows from the inlet and through the two course nest of tubes to the rear end of the condenser, coming back through the upper nest to the outlet 8.

The advantages of my invention will be readily understood by those familiar with the operation of condensers of this type, since it greatly increases the size to which such condon-sers may be constructed and operated in an efficient manner.

I claim:

l. A surface condenser having a steam inlet and an upper and a. lower nest of tubes, said condenser having a chamber for admitting fluid directly from the steam inlet to substantially the whole of that portion of the perimeter including the sides and top of the tube nest facing the steam inlet, and inclined baliles intermediate said tube nests, said tube nests `being sepa-rated by a substantial horizontally extending space, substantially as described.

2. A surface condenser having two nests of t-ubes, one substantially semi-circular and the other comprising two substantially triangular sections iwith a steam passage between the nests and between the substantially triangular sections, substantially as described.

3. A surface condenser having two nests of tubes with a substantial space between them in open-communication with the steam space offthe condenser, means for directing condensate from the upper nest across said space, and a walled conduit for causing air and noncondensible gases withdrawn from both nests to flowover tubes in the nest through which water lis first circulated, substantially as described.

4. A surface condenser having a steaminlet'and a plurality of tube nests, said condenser having a chamber for admittingr fluid direct from the steam inlet to substantially the whole of the portion of the perimeter including the sides and top of one of said nests facing the steam inlet, and downwardly and outwardly7 inclined baffles arranged to form separate flow paths for the different nest-s,

and providing an air olftake therebetween.

5. In a condenser, nests of tubes therein, there being a substantial space between said nests, a flow conduit for conveying fluid to a point adjacent the flow terminus of one of saidnests, and a gas ofltake, non-condensible gases from said conduit and from said last mentioned nest traversing a portion of said last mentioned tube nest before entering said oE-talre, substantially as described.

6. In a condenser, a top tube nest, a bottom tube nest, there being a substantial space between said nests, and a conduit for fluid terminating adjacent the end of the condensing Zone in said bottom nest, there being a space at the lower portion of said bot-tom nest through which condensible vapors flow, fluid from said conduit being adaptedto t `averse said space, substantially asdescribed.

7. In a condenser, a condenser shell, nests of tubes in which fluid flows substantially from top to bottom of said nests, there being a substantial space between said nests, and a conduit for conveying and discharging fluid adjacent the bottom of the lowermost nest in the condenser, substantially as described.

8. In a surface condenser, al shell, an upper and lower nest of tubes, baffles under the upper nest of tubes terminating in a walled conduit leading from the. uppernest to the lower nest, therebeing a chamber in said shell in open communicationwith the vapor' inlet Vof the condenser, and said baffles being inclined to cause a portion of the condensate from said upper nest to flow to said chamber, substantially asdescribed.

9. In a surface condenser, a shell having an inlet and a flow terminus adjacent thebottom of theshell, anest of tubes, there being means for conductingfluid from said inlet to a point beneath said nest of tubes, means for conducting condensate from said nest of tubes in such manner thatit will flow through said fluid, and a common gas oft-take adjacent the bottom of the condenser, aiportion of the'non-condensible gases from the fluid traversing the tubes adj acentthe lower region of the condenser combining with and being withdrawn with the non-condensible gases from the upper region of the condenser through said olf-take, substantially as described.

10. In a surface condenser having an inlet for steam and a flowterminus adjacentthe bottom thereof and provided with a chamber in communication with the steam inlet, tubes, and means for causing the condensate to flow through said chamber in direct communication with the steam from said inlet, the vapor and non-condensible gases from said chamber traversing a portion of the tubes adjacent the flow terminus, substantially as described.

ll. In a surface condenser, a shell having a steam inlet, a tube nest having aflow terminus adjacent the bottom of the shell, there being a chamber in said shell in communication with said inlet, and means for causing condensate to flow through said chamber, Vapor and noncondensible gases from said chamber and from the upper portion of the condenser traversing that portion of the condenser adj acentithe flow terminus, substantially as described.

12. In a surface condenser having an inlet for steam and a flow terminus adjacent the bottom thereof and provided with` a chamber in communication with the steam inlet, tubes, and means for causing condensate to flow through said chamber in direct communication with the steam from said inlet, the va or and non-eondensible gases from said cham er traversing a portion of the tubes adj aeent the flow terminus, said condenser having a Walled 5 passage leading through the tubes to a point adjacent the flow terminus, substantially as described.

13. In a surface condenser, tWo nests of tubes having a substantial space bet-Ween 10 them in open communication with the steam space of the condenser, means for passing cooling Water through the tube nests in series, and a Walled conduit for causing air and non-condensable gases Withdrawn from one nest to flow over tubes in the nest through which Water is irsteirculated, substantially as described.

In testimony whereof, I have hereunto set my hand.

- RAYMOND N. EHRI-IART. 

